This invention relates to improvements of melt-blowing processes and apparatuses applying to multiple rows of spinning orifices describes in U.S. Pat. No. 4,380,570 and 5,476,616, which are herewith incorporated as reference. More particularly, it relates to the improvement whereby melt-blowing spinnerettes are mounted on the surfaces of a polygonal melt-blowing extrusion die block thereby spinning thermoplastic fibers away from the center of the polygon at high extrusion rates, said fibers are then being deflected about 90 degrees by an air stream from a circular or polygonal air ring to enhance fiber entanglement and web formation of high bulk and low density.